Lubricating composition and method of lubricating and improving the lubricating properties of oils



Patented Aug. 13, 1936 LUBRICATING COIWPOSITION AND METHOD OF LUBRICATING AND IMPROVING THE LUBRICATING PROPERTIES OF OILS Carl F. Prutton, East Cleveland, Ohio, assignor,

by mesne assignments, to The Lubri-Zol Development Corporation, Cleveland, Ohio, a corporation of Delaware No Drawing. Application, July 10, 1933,

' Serial No. 679,594

49 Claims.

' This application is a continuation in part of my previously filed co-pending applications Ser. No. 463,366, filed June 23, 1930, and Ser. No. 638,599, filed October 19, 1932.

5 This application relates, as indicated, to a lubricating composition and a method of lubrication and/or method of improving the lubricating properties of lubricating oils and more particularly the invention relates to high pressure lubrication, i. e., lubrication of relatively moving metallic surfaces where the unit area pressure between such surfaces is in the neighborhood of or in excess of approximately 10,000 lbs. per square inch.

15 As has been explained by specialists in this particular field of the art, a lubricant employed for the purpose of reducing friction between relatively moving metallic surfaces may functionin the two ways commonly referred to as thick-film lubrication and thin-film lubrication.

In thick-film lubrication the bearing surfaces are completely separated bya relativelythick continuous film of the lubricating composition employed. When friction between the moving parts 25 is measured in this case, theresults obtained are independent of all factors except pressure, speed and the viscosity of the lubricating composition employed. A single curve representing all data is found by plotting the coefilcient of friction 30 against a function consisting of the product of viscosity and speed divided by pressure per unit area, as long as the value of such function is greater than a definite amount. At this minimum point, reduction of viscosity or speed or increase 35 in pressure results in arupture of the film of lubricant. Although the value of the coeflicient of frictionis lowest at the point atwhich the film is about to fail, the increase in the coeflicient of friction for higher viscosity and speed, or lower 4Q pressure, is relatively slight. The conditions resulting in thick-film lubrication are therefore those which result in low friction.

For pressures sufficiently great or for bonespondingly low values of viscosity or speed, the

film of lubricant, as above indicated, is ruptured.

-' but although such film is ruptured, it is not entirely destroyed and the metallic bearing surfaces are still affected to some extent at least by the presence of the lubricant. This condition is 50. commonly referred to as ,thin-fllm lubrication. 1 when one of the bearing surfaces is a-bearing metal such as bronze or babbitt, seizure does not take place at once. but the coemcient of friction increases rapidly to abnormally high values with 55 each slight further increase in pressure or decrease in viscosity or speed. For a given set of bearings, the data obtained for thin-film lubrication may be approximately co-ordinated into a single curve, but only on plotting coefficient of friction against the product of viscosity and speed 5 divided by a power of the pressure lying between zero and one. If both bearing surfaces are of steel, seizure or scoring will result almost immediately upon failure of thick-film lubrication when a pure mineral oil is the sole lubricating composition employed.

It is among the objects of my invention to provide a lubricating composition and a method of v improving the lubricating properties of a .lubricatingoil, such as pure mineral oil, particularly to increase the breakdown pressure of the film of such oil between bearing surfaces and consequently to improve the thin film lubricating characteristics of the oil.

It is a further object of my invention to im-, prove the lubricating properties of lubricating oils and to provide a method of lubricating relatively moving metallic surfaces by such means as will function in a fashion different from the accepted manner in which lubricating oils have been relied upon to reduce the friction between moving metallic parts. This invention contemplates the employment of an additional means assisting the lubricating oil in maintaining the proper separating film between the relatively moving surfaces. This invention contemplates the employment of certain halogen bearing materials which will react chemically with the rela-- tively moving metallic surfaces, particularly under the conditions imposed by such relative movement, to create a film between such surfaces, which film is distinct from the film of pure lubricating oil which has been relied upon in the past to prevent the bearing Si faces from scoring even under such extreme pressure conditions as result in thin-film lubrication, as above pointed out. [I am awareof the fact that the addition of halogen bearing ingredients to a lubricating oil is broadly not new. In .order that the present invention may be more clearly understood. brief reference will be had to the principal 'prior art patents pointing out what is believed to have been their contribution to the art so that the field to which the present invention relatesmay be more readily understood.

J. W. Aylgworth in his Patent No. 1,029,254 suggested thejuse offa lubricating agent which has thephyslcal property of being non-inflammable or difdcultly inflammable imparted to it, whereby the danger from fire in situations in which suchlubricant is used is greatly minimized (page 1, lines 9 to14). Aylsworth suggested for use as lubricants certain halogen substitution products of carbocycllc compounds, and further suggested the combination with such compounds of a quantity of different grades of machinery oils, but the minimum amount of such carbocyclic compounds which Aylsworth suggested would be necessary in order to render his composition non-inflammable, and to thereby achieve the purposes of his invention, is at least 30 per cent of the total composition. Aylsworth was successful in producing a lubricating composition which is substantially non-inflammable and he therefore taught a particular manner in which this end might be achieved.

Certain other patents have been granted to Aylsworth, but they all center around the problem of rendering a lubricating composition relatively non-inflammable so that it may be employed in the presence of open flame and similar regions of high temperature without burning.

The principle taught by Aylsworth, i. e., the use of certain halogen compounds for the purpose of providing a non-inflammable lubricant or one capable of withstanding high temperatures, has been followed in the development oi the art since his invention, as for example U. S. Patent No. 1,668,022 to Midgley.

I am also aware of the fact that it has been suggested in the prior art (U. S. Patent No. 1,796,857 to Barnard) to add small proportional amounts of materials such as carbon tetrachloride to a lubricating oil, but for the purpose of reducing the viscosity of the oil to such an extent as to facilitate the starting or turning over of internal combustion engines at relatively low temperatures; the carbon tetrachloride or similar compound when the engine became heated being volatilized and leaving only the pure mineral oil with the higher viscosity necessary for continuous operating temperatures.

The additions to lubricating oils which I now propose and by which the objects of this invention may be attained have also been used to a certain extent as additions to electrical insulating oils particularly adapted for use in transformers where it was sought to render such oils non-inflammable, or for use in circuit breakers, etc., to reduce the amount of gas generated by arcing.

It is the principal object of my invention, therefore, to provide a method of lubricating and a method of improving the lubricating properties of lubricating oils by adding thereto relatively small amounts of certain halogen bearing ingredients which are active under the conditions imposed by relative movement between the bearing surfaces to chemically act upon such surfaces to produce a secondary film, as previously explained, but using such additions in percentages much lower than suggested in the prior art, as exemplified by the teachings of Aylsworth, in order to secure the desired improvement in the thin-film lubricating properties of the oil without such a reduction in the viscosity of the com.- position which would detract from its "thickfilm" lubricating properties. It is also essential that the additions have a relatively high boiling point i. e., low vapor pressure so as not to be driven off during use at elevated temperature.

While the exact nature of the reaction between the halogen compounds and the metallic bearing surfaces is not fully understood, it is believed that the same is clearly a. chemical action as indicated by an examination of the bearing surfaces. However, since this action is of the surface-reaction type it may perhaps be more accurately defined as a physico-chemical reaction.

Other objects of my invention will appear as the description proceeds.

To the accomplishment of the foregoing and related ends, said invention, then, consists .of the steps hereinafter fully described and particularly pointed out in the claims, the following description setting forth in detail one approved method of carrying out the invention, such disclosed method, however, constituting but one of the varlous ways in which the principle of the invention may be used.

My invention, as above explained, contemplates the addition to a suitable oil base of minor proportions oi halogenated compounds in such proportions as not to materially reduce the viscosity oi the oil. Since the loss oi such additions by volatilization will, in general, be less for higher boiling materials, the boiling point or temperature at which the vapor pressure reaches atmospheric pressure should be above 140 C.

The base of the lubricating composition is some oily material, such as mineral 011. There are three factors which determine the type of the halogenated carbon compounds which may be employed, via, stability, boiling point, and effect on the viscosity of the resultant composition.

The halogenated compounds used are preferably of such a nature as to be sufilciently stable, or to resist hydrolysis in the presence of moisture, so that they will not cause corrosion of the bearlugs and other-metallic parts exposed to the lubricant; that is, they will not chemically react to any substantial extent with such metallic parts excepting under conditions of extreme pressure and the like as above indicated. These requirements, in general, are met more specifically by halogenated carbon ring compounds as distinguished from open chain compounds. The chlox'inated species of these carbon compounds is preierred, particularly due to their low cost and superiority of performance. As above indicated, the halogenated carbon ring compounds added to the oil base are preferably of the chlorinated species and particularly the following compounds have been found to produce very satisfactory results, viz., halogenated, or more specifically,

chlorinated benzene compounds, such as, di-chlorbenzene, notably the ortho compound;' chlorinated naphthalene; chlorinated dlphenyl; halogenated, or more specifically, chlorinated homologs of the above such as toluene, methyl naphthalene, and phenyl toluene; chlorinated derivatives of benzene, naphthalene and diphenyl, such as aniline, naphthyl amine and phenyl aniline.

Of the chain compounds which may be employedsuch as acetylene tetrachloride, butylene dichloride (1-2 di-chlor-butane) monochlorhexane, 1-2 dichlor hexane, (specifically, those having a vapor pressure less than atmospheric at a temperature of 140) etc. or any other halogen substitution or addition products of the paraflins, olefines or acetylenes or derivatives of them, the less volatile and more stable are preferred for the reasons above set forth;

It is to be noted that the above enumerated examples of halogenated organic compounds useful as extreme pressure addition agents in accordance with this invention are compounds of the type which may be produced by direct halogena- 7 such as sulphur chloride and from which products the sulphur-bearing or other unstable constituents have .not been removed.

As particularly pointed out herein, the addition agents used,in order that they may not be vola-' tilized during use under high temperatures, should have a vapor pressure less than atmospheric. at

' a temperature of 140 C. It will also be noted that numerous specific examples given, such as orthodichlorbenzene, the chlorinated naphthalenes and dlphenyls, as well as their derivatives, have a vapor pressure less than atmospheric at 170 C.

In addition, all of the specifically named compounds and groups of compounds suitable as addition agents to lubricating compositions according to, the presentinvention are substantially stable, non-corrosive, and miscible or soluble in mineral oil, 'at least to the extent necessary to produce lubricants of the type herein contemplated.

By the term oil-soluble as used herein and in the claims is meant that property of the examples of addition agents disclosed herein which enables the same to be included, at least the range of quantities herein contemplated, in a lubricating oil base such as mineral oil to produce a substantially permanently homogeneous lubricating composition amounts of base compounds which may be rea It will be noted thatcertain of the specifically mentioned compounds such as acetylene tetra chloride, butylene dichloride, etc., contain considerably more than 50% halogen. Compounds of this character, 1. e., compounds which contain more than 50% halogen are useful .as extreme pressure addition agents to lubricating compositions since they enable the use'of small tively expensive as carriers for substantial amounts of the halogen which is relied upon .to impart the extreme pressure characteristics to the final composition.

Since the addition of compounds of the class including the above enumerated will usually reduce the viscosity of the oil base to which the same are added, if a large percentage of such compounds are added, there will bea tendency to destroy thick-film lubrication because of the reduction inviscosity of the composition. If an excessive quantity of such compoundsare added, all of thelubrication will then be of the thinfilm type and therefore produce a decided increase-in the total amount of friction developed.

attained by using minihalogenated compounds Optimum results are mum quantities of these so that their beneficial efifect will not be overing the viscosity of shadowed by their detrimental effect in reducthe composition. For ordinary uses or normal lubrication, the resultant composition will have inferior lubricating properties if the loss of viscosity is too great, such as would result from the use of more than 20% of halogenated compounds of any type.

My invention, "therefore, contemplates adding to a suitable oil base halogenated'carbon com-- pounds having a boiling point over degrees .10% to 20% of the total composition. j'

The optimum amount of the halogenated compound to be employed will depend upon the chemical activity .of the particular compound as well as its physical characteristics including its effect on the viscosity of the oil to which it is added and the particular use for which the lubricant is intended. The reason that the chemical activity of the compoundadded determines the character and amount of such addition which should be'used with the oil is due to the fact that a sufllcient amount of.the proper type must be present in order to react chemically under operating conditions with the bearing surfaces under operating conditions only to produce the vso-- called secondary film. The. upper-limit of the amount of addition, agent employed is, as previously explained, determined by the effect of the 15 addition upon the viscosity of the oil.

Extremely active compounds may 'be effective to accompl sh the purposes of this invention when present in amounts even less than the above referred to minimum amount of 0.10%.

Thepresence of this secondary film can readily be determined by suitable test of metallic bearings operating with a lubricant of the above defined character. and then scraping oif the film which has been formed on the bearing surfaces L and which upon chemical analysis will show the presence of the halogen in inorganic form.

For the purpose of lubricating and reducing the friction between the relatively moving parts of an internal combustion engine, such as crank I case bearings, piston and cylinder surfaces, as well as piston rings and val es, my invention contemplates adding to a suitable oil base, such as mineral oil, concentrations of from .10% to 2% of halogenated compounds containing from 50 1 to 25% of chlorine. If the valvestructure of the engine'is to be lubricated separately from the remainder of the mechanism or by means acting in an auxiliary fashion, the lubricating composition between the moving surfaces will preferably contain a larger amount of such halogen- 'ated compounds, 1. e., from 1% to 10%.

The invention described herein has a particular advantage in the tendency of the compoundedlubricant employed to keep down the carbon formation and hence this method is particularly applicable for improving the lubricating properties of a lubricating oil employed as the lubricant for the upper parts, i. e., pistons, valves,

pistons rings, etc., of an internal combustionengine by dissolving the specified composition in the'motor fuel so that such fuel when introduced in to the combustion chamber is volatilized and the lubricating composition distributed over the .walls of such chamber as well as the valves and their associated parts.

My invention has certain definite advantages, of whichthe following may be mentioned;

First: By this invention it is possible to extend the pressure range because of the reduced tend ency for bearing surfaces to become scored or to seize at higher pressures than are allowable with ordinary lubricants.

Second: The friction is reduced, especially in the higher pressure range below that obtained 65 with ordinary lubricants.

The subject-matter of this application is re- "lated to the subject-mattenof my co-pending ap plication Ser. No. 635,701, filed September 30, 1932.

Other modes of applying ,the principle of my 70 invention may be employed instead of the one explained, change being made as regards the method herein disclosed, provided the step'or steps stated by any of the following claims or the 7 equivalent of such stated step or steps be employed.

I, therefore, particularly point out and distinctly claim as my invention:

1. As a composition of matter, a lubricating composition having as a principal lubricating constituent the combination of mineral oil and from about one-tenth per cent. to twenty per cent., based on the amount of such mineral oil,-

of a halogenated organic compound having a boiling point over 140 C. I

2. As a composition of matter, a lubricating composition having as a principal lubricating constituent the combination of mineral oil and from about one-tenth per cent. to twenty per cent., based on the amount of such mineral oil, of a chlorinated organic compound having a boiling point over 140 C.

3. As a composition of'matter, a lubricating composition having as a principal lubricating constituent the combination of mineral oil and from about one-tenth per cent. to twenty per cent., based on the amount of such mineral oil, of a chlorinated organic compound having a boiling point over 170 C.

4. As a composition of matter, a lubricating composition having as a principal lubricating constituent the combination of mineral oil and from about one-tenth per cent. to twenty per cent., based on the amount of such mineral oil,

of a stable, oil-soluble, halogenated organic com- 7 pound having a vapor pressure less than atmospheric at 140 C.

5. As' a composition of matter, a lubricating composition having as a principal lubricating constituent the combination of mineral oil and from about one-tenth per cent. to twenty per cent., based on the amount of such mineral oil,

of a stable, oil-soluble, chlorinated organic compound having a vapor pressureless than atmospheric at 140 ('2.

6. As a composition of matter, a-lubricating composition having as a principal lubricating constituent the combination of mineral oil and from about one-tenth per cent. to two per cent., based on the amount oi such mineral oil, of an oil-soluble, halogenated organic compound hav hi?) a vapor pressure less than atmospheric at 1 C.

'7. As a composition of matter, a lubricating composition having as a principal lubricating constituent the combination of'mineral oil and from about one-tenth per cent. to two per cent., based on the amount of such mineral oil, of an oil-soluble, chlorinated organic compound having 'a vapor pressure less than atmospheric at 140 C.

8. As a composition of matter, a lubricatingcomposition having as a principal lubricating constituent the combination of mineral-oil and from about one-tenth per cent. to two per cent.,

based on the amount of such mineral oil, of an oil-soluble, chlorinated organic compound having a vapor pressure less than atmospheric at 170' C.

9. As a composition of matter, a lubricating composition having as a principal lubricating constituent the combination of mineral oil and from a minimum eifective amount to about two per cent., based on the amount of such mineral oil, of a stable, oil-soluble, halogenated organic compound having a vapor pressure less than atmospheric at 0., and .containing from about twenty-five per cent. to about fifty per cent. halogen.

10. As a compositiomof matter, a lubricating of 140 C. and present in an amount less than composition having as a principal lubricating constituent the combination of mineral oil and from a effective amount to about two per cent., based on the amount of such mineral oil, of an oil-soluble, chlorinated organic com- 5 pound having a vapor pressure less than atmospheric at 140 0., and containing from about twenty-five per cent. to about iifty per cent. 1 chlorine. V

11. As a composition of matter, a lubricating o composition having as a principal-lubricating constituent the combination of mineral oil and from about one per cent. to ten per cent., based on the amount of such mineral oil, of an oilsoluble, halogenated organic compound having a 15 vapor pressure less than atmospheric at 140 0.

l2. As a composition of matter, a lubricating composition having as a prinicipal lubricating constituent the combination oi mineral oil and from about one per cent. to ten per cent., based go on the amount of such mineral oil, of an oilsoluble, chlorinated organic compound having a vapor pressure less than atmospheric at 140 C. 13. As a composition of matter, a lubricating composition having as a principal lubricating 25 constituent the combination of mineral oil and from about one per cent. to ten per cent., based on the amount of such mineral oil, of an oilsoluble, chlorinated organic compound having a vapor pressure less than atmospheric at C. 30

14. As a composition of matter, a lubricating composition having as a principal lubricating constituent the combination of mineral oil from about one-tenth per cent. to twenty per cent., based on the amount of such mineral oil, of an 35 oil-soluble, halogenated organic compound having a vapor pressure less than atmospheric at 140 0., and containing from about twenty-five per cent. to about fifty per cent. halogen.

15. As a composition of matter, a lubricating composition having as a principal lubricating constituent the combination of mineral oil and from about one-tenth per cent. to twenty per cent., based on the amount of such mineral oil, of a stable, oil-soluble, chlorinated organic compound having a vapor pressure less'than atmospheric at 170 C., and containing from about twenty-five per cent., to about fifty per cent. chlorine.

16. A lubricating composition having as a principal lubricating constituent, the combination of mineral lubricating oil and a halogenated organic compound, said compound having a vapor pressure less than atmospheric at a temperature twenty per cent., based on the amoimt ct mineral I oil, but sumcient to provide a lubricating composition eifective to prevent seizure and scoring of relatively moving metallic surfaces under pressures substantially in excess of 10,000 pounds per 60 square inch.

1'1. A lubricating composition but; as a principal lubricating constituent. the combination of' mineral lubricating oil and a stable, til-soluble, chlorinated organic having more than twenty-five per cent. chlorine and a vapor pressure less than ahnospheric-at a temperature of 170 C. and presmt in an amount less than ten per cent., based on the amount of mineral oil, but sufiicient to provide a lubricating composition effective to prevent Seizure and scoring of relatively moving metallic surfaces under pressures substantially in excess of 10,000 pounds per square inch.

18. .As a composition of matter, a lubricating :5

compound. said compound stituent the combination of mineral oil and from composition having as a principal lubricating conabout one-tenth per cent. to twenty per cent., based on the amount of such mineral oil, of a stable, oil-soluble, halogenated hydrocarbon havirg a vapor pressure C.

19. As a composition of matt r, a lubricating composition having as a principal ubricating constituent the combination of mineral oil and from from one-tenth per cent. to twenty per cent., based on the amount of such mineral oil, of a stable oil-soluble, chlorinated hydrocarbon having a vapor pressureless than atmospheric at 140 C. 20. As a composition of matter, a lubricating compositionhaving as a principal lubricating constituent the combination of mineral oil and from about one-tenth per cent. to two per cent., based on the amount of such mineral oil, of a stable, oil-soluble, halogenated hydrocarbon having a vapor pressureless than atmospheric at 140 C. 21. As a composition of matter, a lubricatin composition having as a principal lubricating constituent the combination of mineral oil and a minor proportion, based on the amount of such mineral oil, of a halogenated open-chain'organic compound having a boiling point over 140 C. i

22. As a composition of matter, a lubricating composition having as a. principal lubricating constituent thecombination of mineral oil and a minor proportion, based on the amount of such mineral oil, or a chlorinated open-chain organic compound having a boiling point over 140 C.

23. As a. composition of matter, a. lubricating composition having as a principal lubricating constituent the combination of mineral oil and a minor proportion, based on the amount of such mineral oil, of a chlorinated'open-chain organic compound having a boiling point over C.

24. As a composition of matter, a lubricating composition having as a principal lubricating constituent the combination of mineral oil and from about one-tenth per cent. to twenty per cent., based on the amount of such mineral oil, of a stable, oil-soluble, halogenated open-chain organic compound having a vapor pressure less than atmospheric at 140 C.

' 25. As a composition of matter, a lubricating composition having as a principal lubricating constituent the combination of mineral oil and from about one-tenth per cent, to twenty per cent.,

based on the amount of such mineral oil, of a stable, oil-soluble, chlorinated open-chain organic compound having a vapor pressure less than atmospheric at 140 C.

26. As -a composition of matter, a lubricating composition having as a principal lubricating constituent the combination of mineral oil and from about one-tenth per cent. to twenty per cent., based on the amount of such'mineral oil, of a. stable, oil-soluble, halogenated open-chain organic compound having a vapor pressure less than atmospheric at 140 C.,-and containing from about twenty-five per cent. to about fifty per cent.

halogen. v

27. As a composition of matter, a lubricating composition having as a principal lubricating constituent the combination of mineral oil and from about one-tenth per cent. to twenty per cent., based on the amount of such mineral oil, of a stable, oil-soluble, chlorinated open-chain organic compound, having a'vapor pressure less than atmospheric at 140 C.', and containing from chlorine.

less than atmospheric at 28. Ass. composition or matter, a lubricating composition having as a principal lubricating constituent the combination of mineral oil and from about one-tenth per cent. to twenty per cent., based on the amount of such mineral-oil, of a 5 stable, oil-soluble, chlorinated open-chain organic compound, having a vapor pressure less than atmospheric at 170 C., and containing from about twenty-five per cent. to about fifty per cent.

chlorine.

29. As a composition'of matter, a lubricating composition having as a principal lubricating conv stituent the combination of mineral oil and from about one-tenth per cent. to two per cent., based on the amount of such mineral oil, of a stable, 1 oil-soluble, halogenated open-chain organic compound having a vapor pressure less than atmospheric at 140 C.

39. As a composition of matter, a lubricating. composition having as a principal lubricating con- 20 stituent the combination of mineral oil and from about one-tenth per cent. tov two per cent., based on the amount of such mineral oil, of a stable, oilsoluble, chlorinated open-chain compound having a vapor pressure less than atmospheric at 140 31. As a composition of matter, alubricating composition having as a principal lubricating constituentthe combination of mineral oil and from about one-tenth percent. to two per cent., based 0 on the amount of such mineral oil, of a stable, oilsoluble, chlorinated open-chain organic compound having a vapor pressure less than atmospheric at 170 C.

32. As a composition of matter, a lubricating composition having as a principal lubricating constituent the combination of mineral oil and from about one percent. to ten per cent., based on the amount of such mineral oil, of a stable, oilsoluble, halogenated open-chain organic compound having a vapor pressure less than atmos- 4o pheric at 140 C.

33. As a composition of matter, alubricating composition having as a principal lubricating constituent the combination of mineral oil and a minor proportion, based on the amount of such 45 mineral oil, of at least one compound of the class consisting of halogen substitution and ad dition products of the parafllns, olefines, acetylenes, and derivatives of such .hydrocarbons, such halogen compounds having boiling points over 50 I 34. As a composition of matter, a lubricating composition having as a principal lubricating constituent the combination oi. mineral oil and from about one-tenth per cent. to twenty per cent., based on the amount of such mineral oil, m5

of at least one stable, oil-soluble, compound of v the class consisting of halogen substitution and addition products of the parafflns, oleflnes, acetylenes, and derivatives of such hydrocarbons, such halogen compounds having vapor pressures-7o less than atmospheric at 140 C. a

36. As a composition of matter. a lubricating composition having as a principal lubricating constituent the combination of mineral oil and from about one-tenth per cent. to twenty per 75 acetylenes, and derivatives of such hydrocarbons,

such chlorine compounds having vapor pressures less than atmospheric at C.

37. As a composition of matter, a lubricating composition having as a principal lubricating constituent the combination of mineral oil and from aboutone-tenth per cent. to two per cent., based on the amount of such mineral oil, of at least one stable, oil-soluble, compound of the class consisting of halogen substitution and addition products of the parafllns, olefines, acetylenes, and derivatives of such hydrocarbons, such halogen compounds having a vapor pressure less than atmospheric at 140 C.

88. As a composition of matter, a lubricating composition having as a principal lubricating constituent the combination of mineraloil and from about one-tenth per cent. to two per cent., based on the amount of such mineral oil, of at least one stable, oil-soluble compound of the class consisting of chlorine substitution and addition products of the parafilns, olefines, acetylenes, and

derivatives of such hydrocarbons, such chlorine compounds having vapor pressures less than atmospheric at 140 C.

39. As a composition of matter, a lubricating composition having as a principal lubricating constituent the combination of mineral oil and from about one per cent. to ten per cent., based on the amount of such mineraloil, of at least one stable, oil-soluble compound of the class consisting of halogen substitution and additionproducts of the parafiins, olefines, acetylenes, and derivatives of such hydrocarbons, such halogen compounds having vapor pressures less than atmospheric at 140 C.

40. As a composition of matter, a lubricating composition having as a primary. lubricating constituent the combination of mineral oil and a minor proportion based on the amount of such mineral oil of at least one compound of the class consisting of acetylene tetrachloride, butylene dichloride, monochlorhexane and dichlorhexane.

41. As a composition of matter, a lubricating composition having as a principal lubricating constituent the combination of mineral oil and a minor proportion, based on the amount of such mineral oil, of chlorinated hexane.

42. As a composition of matter, a lubricating composition having as a principal lubricating constituent the combination of mineral oil and a total of about one-tenth per cent. to less than twenty per cent., based on the amount of such mineral oil, of halogenated organic compounds having vapor pressures less than atmospheric at 140 C.

43. As a composition of matter, a lubricating composition having as a principal lubricating constituent the combination of mineral oil and from one-tenth per cent. to twenty per cent.,

quantities less based on the amount oi. such mineral 011,012 a halogenated organic compound having a vapor pres sure of less than atmospheric at140 C. and containing more than fifty per' cent halogen.

, 44. The method of reducing friction between relatively moving metallic surfaces which comprises maintaining therebetween a film of lubricating oil and at the same time chemically acting upon said surfaces by means of a halogen ated organic constituent in said 011 film having .a vapor pressure less than atmospheric at 140 C.

and present in said oil film than about twenty per cent.

45. The method of reducing friction between relatively moving metallic surfaces which comprises maintaining therebetween a film of lubricating oil and at the same time chemically acting upon said surfaces by means of a halogenated hydrocarbon constituent in said, oil film having a vapor pressure less than atmospheric at 140 C. and present in said oil film in quantities less than about twenty per cent.

46. The method of reducing friction between relatively moving metallic surfaces which comprises maintaining therebetween a film'of lubri cating oil and at the same time chemically acting upon said surfaces by means of a halogenated organic constituent in said oil film having a vapor pressure less than atmospheric at 140 C. containing more than twenty-five per cent. halogen and present in said oil film in quantities less than about twenty per cent.

47. The method of reducing friction between relatively moving metallic surfaces which comprises maintaining therebetween a film of lubricating oil and at the same time chemically acting upon said surfaces by means of a halogenated organic constituent in said oil film having in quantities less a vapor pressure less than atmospheric at 140 C.

containing more than twenty-five per cent. halogen and present in said oil less than about ten per cent.

48. The method of reducing friction between relatively moving metallic surfaces which comprises maintaining therebetween a film of lubricating oil and at the same time chemically acting upon said surfaces by means of a halogenated open-chain organic constituent in said oil film having a vapor pressure less than atmospheric at 140 C. and present in said oil film in than about twenty per cent.

49. The method of lubricating relatively mov ing metallic surfaces which comprises maintaining therebetween a film of lubricating oil and at the same time chemically acting upon such surfaces by means of a stable, oil-soluble, chlorinated organic constituent in said oil film, said constituent containing more than twenty-five per cent. chlorine, having a vapor pressure less than atmospheric at C. and present in said cent.

CARL F. PRUTTON.

' oil film in quantities less than about ten per 

